Electric attachment fitting



NOV. PETRY ELECTRIC ATTACHMENT FITTING Filed Aug. 5, 1941 2 Sheets-Sheet; 1

INVENTOR. JOHN FT/Q) flTTORNEV NOV 17, 1942. J PETRY ELECTRIC ATTACHMENT FITTING Filed Aug. 5, 1941 2 Sheets-Sheet 2 1477'0PNE) Patented Nov. 17, 1942 UNITED ELECTRIC ATTACHMENT FITTING John Petry, Flushing, N. Y., assignor to Raylite Electric Corp., a corporation of New York Application August 5, 1941, Serial No. 405,459

9 Claims. (01. 173361) This invention relates to electric attachment fittings, such as cap-plugs and the manufacture thereof, said fittings serving to detachably connect portable electric applian ces, lighting systems and the like, to an electric power supply outlet receptacle in the well understood manner.

Among the objects of the invention is to generally improve electric attachment fittings of the character described, which shall comprise few and simple parts assembled to form a neat appearing, compact, rugged structure, which shall be cheap and easy to manufacture, and which shall be practical and efficient to a high degree in use.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combination of elements attachment, cap-plug with the body. portion and arrangement of parts which will be exemplified in the construction and method of manufacture hereinafter described and of which the scope of application will be indicated in the following claims.

This application contains in part subject matter described and shown in my Letters Patent No. 2,244,527, issued June 3, 1941, for Currenttapping cap-plug fitting and like attachment devices.

In the accompanying drawings, in which is shown various possible illustrative embodiments of this invention,

Fig. 1 is a view showing a development plan layout of a plug cap terminal blade in the manufacture thereof embodying the invention; I

Figs. 2 and 3 are front and side elevational views, respectively, of the terminal blade in completed form after being cut, folded and bent from the layout shown in Fig. l;

, Fig. 4 is a sectional view taken through a onepiece insulating body portion of the improved cap-plug showing the conductor wires and one layout of modified form of a plug cap terminal shown in Fig. 13 completely assembled with the terminal. blades shown in Figs. 1i and 12 and connected in circuit with conductor wires, and

Fig. 16 is a cross-sectional view taken on line l6l6 in Fig. 15.

Referring in detail to the drawings and as shown in complete assembly in Fig. 6, 2!! denotes an improved attachment cap-plug fitting constructed to embody the invention adapted to be connected with a conventional base board or flush outlet receptacle of a suitable electric power supply (not shown), in the well understood manner, through spaced terminal blades 2| extending from insulation body portion 22, said fitting 20 being applied to the ends of conductorof sheet metal, such as brass or bronze having a thickness of substantially one-half of that required for the final structure and should preferably be sufilciently resilient to have inherent spring in single thickness and in double thick ness to be rigid enough to withstand bending and rough usage as the projection portion of such blades 2|.

The manufacture of said terminal blades 2| may be carried out as follows: The single thickness sheet metal from which the blades 2| are formed may be each substantially rectangular shaped, as for example, strip S, punched or blanked out as shown as in Fig. l, with the upper portion U thereof provided if desired, with a cir-- cular opening 2|a above a crease line, XX. The mid-portion M of said strip S below said line XX, however, is cut to form a downwardly extending tongue 2lb, while the lower portion L thereof spaced from the tongue 2Id is provided with punched slit formed with upper and lower piercing prongs 2|c and 2|d, respectively, spaced on opposite sides of another crease line YY, said lower portion also having another tongue 2|e out to extend downthereon, spaced from the prongs 2| d.

When the upper portion U of strip S is down folded on the crease line XX so that said upper portion U extends along the mid-portion M, a bight at the leading end 2|f is formed and by leaving said upper portion U slightly divergent with respect to the mid-portion M, a spring contact is provided which terminates just short of the plane of the upper face 22a of the insulating body portion 22 as shown in the assembly in Fig. 6.

The lower portion L is upfolded on the crease line YY so as to double the thickness and stiffen the base end 2 g of the blade 2| and at the same time also arranges and locates the upper and lower piercing prongs 2|c and 2|d in a recessed superimposed spaced or staggered relation to terminate said base end 2|g. Thus if the upper prongs 2 le comprise a set of three sharp pointed teeth and the lower prongs 2 hi comprise a set of two of such teeth, then the above described folded structure provides a series of five spaced staggered teeth as shown in- Figs. 2 and. 9. The tongues 2|b and 2|e may each be bent or sprung out of the planes of the mid-portion M and lower portion L, respectively, from opposite sides, so that the downwardly extending tongue 2|b may serve as a contact means for connecting with the ends 23a of conductor wires 23 and so that the tongue 2|'e, upwardly extending from the upfolded lower portion L, may serve as a spring wedging means for irremovably securing the blade base in anchored position in the body portion 22, all as hereinafter described and shown in Fig. 6.

The insulating body portion 22 of the fitting 20 preferably is a one-piece structure of suitable shape and formed of so-called plastics, as for example, a phenol-condensate product or the like moldable substances which provides a rigid finish structure.

As shown in Figs. 4, 5 and 6, the blades 2| are mounted and secured to extend upwardly from the top side 22a of body portion 22, the base ends 2|g of said blades 2| being fitted into spaced sockets or cavities 22b extending in from said top side 22a. Said sockets 22b are each molded with a shoulder or ledge 22c adjoining a wall 22d, said walls 22d merging in a tapered portion or end 226 to permit through passage of the separate leads of the conductor wires 23, the latter being inserted in a central passage 22; extending in from the bottom side 22g of the body portion 22 opposite the top side 22a. Walls 22h of the passage ftZe may be in substantial alignment with the walls 22d of sockets 22b to facilitate the core molding operation in manufacturing the body portions 22 to provide branch communication between th passage 22f and spaced sockets 2272.

With blades 2| manufactured as above described as shown in Figs. 1 to 3, the fitting 20 may have the parts assembled and connected with the conductor wires .23 by inserting the ends 23a of a conductor ire lead from the body portion lower side 22g through the passage 22f and into the branched sockets 22b. If desired, said ends 23a are bared of insulation for a short distance and are preferably extended to approximately above the level of the body portion top side 22a as shown in Fig. 1. The blades 2| can now be fitted into the sockets 22?) from said top side 22a and are pushed'down until the piercing prongs 2|c and 2|d at the base end 2| g of the blades 2| cut through the insulation of the conductor wires 23 and make electric contact connection with the stranded core 23b as shown in Fig. 9. This cutting takes place when conductor wires 23 are forced against the bottom of the sockets 22b, and when the tongue 2|e is sprung in moving from the position shown in Fig. 4 to a Wedging position under the body portion ledge 220 for irremovably anchoring the blade base 2 lg rigid in the sockets 22b. The tongue 2|b during the above described anchoring operation may enter a groove 22m provided to extend along each socket 22b to con tact and electrically connect with the conductor wire end 23a which occupies the said groove 22m and at the same time engages said end 23a for firmly wedging the conductor wire 23 about the blade ends 2| g as shown in Figs. 6 and 8. Thus, two electrical connections are provided between the blade ends 2|g and the conductor wire 23. The blade portions U terminating short of the body portion side 22a provide spring adjustment for taking up variation in receptacle outlet plugin connections.

In Figs. 10 to 16, inclusive, there is shown another embodiment of the invention in the manufacture and construction of cap-plug fitting I20, having the blades |2| thereof formed of single thickness material, as strips SI, which are similar in shape and size to strip S described above in connection with fitting 20 but may be made to correspond to the layout shown in Fig. 10.

The strip SI also may comprise an upper portion U| having an opening I 2| a above a crease line XX, a mid-portion Ml having a slit forming a downwardly extending piercing prong |2|b above a crease line YY while a lower portion Ll is provided on upwardly extending piercing prong |2|c below said crease line YY so as to provide a central split between spaced sections |2|e in the manner hereinafter described and shown in Fig. 11. Opposite edges on the lower portion of the mid-portion MI and upper part of lower portion Ll may be cut as at l2 |y' to provide spurs I2|k which are adapted to be anchored under shoulders |22d of an insulating body portion 22 as shown in Fig. 16.

The manufacture of terminal blades |2| is carried out in a manner similar to that for producing blades 2| by punching or cutting strip SI with the layout shown in Fig. 10 and then down folding the upper portion U| on crease line XX to provide a bight at the leading end |2| By leaving said upper portion U| slightly divergent with respect to the mid-portion Ml, a spring contact is provided which terminates just short of a plane of the upper face or side |22a of the body portion I22 like the construction in blades 2| and as shown in Figs. 12 and 15.

The lower portion L| is upfolded on crease line YY so as to double the thickness and stiffen the base end |2|g of the blade |2| and at the same time also arrange and locate the piercing tongues 2 lb and l2 la in spaced relation as shown in Fig. 11. The tongue |2|b may be bent or sprung out of the plane of the mid-portion M| so that said downwardly extending tongue |2|b may serve as a contact means for connection with ends 23a of conductor wire 23 as shown in Fig. 15. The base end |2|g of each blade |2| formed is seen in Figs. 11 and 16 to have spaced apart sections |2|e each terminated by a spur |2|k thus forming a structural portion which is similar in all respects to the base end of the blades fully described and shown in my aforementioned patent.

The insulating body portion I22 of fitting I20 like body portion 22 of fitting 20 may also be made of a plastic molded substance, and as shown in Figs. 13 to 16, inclusive, the blades I2I are mounted to extend upwardly from the body portion top side I22a, the blade base ends I2Ig being fitted into spaced sockets or cavities I22b extending in from said top side I22a. end of each socket I22b is molded with an integrally formed upwardly projecting wedge I22c which is arranged and constructed to spread the spaced sections I2Ie when the base ends I2Ig are inserted fully into the socket I22b as shown in' Fig. 16. The side Walls of the socket I22b extend parallelly in from said top side I22a, the width of said socket being enlarged at the inner ends of said side walls, that is, out back for a length substantially equal to the wedge I22c to top side I22a. The walls I22h of the passage I22f may be in substantial alignment with the upper end of the socket wall I22d to facilitate the core molding operation in manufacturing the body portion I22 to provide a branch communication between the passage I22 and spaced socket I22b.

With the blades I 2| manufactured as above described and shown in Figs. 10 to 12, the fitting I20 may have the parts assembled and connected with the conductor wires 23 by inserting the end 230 thereof in from the body portion lower side I22g through passage I22 and into branched sockets I22b. Like in the assembly of fitting 20, the ends 23a are preferably extended to approximately above the level of the body portion top side I22a. The blades I22 may then be inserted into the sockets I22b from said top side I22a and are pushed down until the piercing prongs I2Ic between the sections I2Ie of the blade base end I2I g cut through the insulation of theconductor wires 23 and make electrical contact connection with the stranded core 23b as shown in Fig. 16.

This cutting takes place when the conductor wires 23 are forced against the wedge I22c at the bottom of the sockets I22b. Said wedges I22c simulta.neous1y enter the split in the base ends I22g r:

and cam the sections I 2 le laterally into the pockets and under the shoulders I22m making an irremovable firm anchorage without scoring or otherwise scratching the walls of said pockets other than tightly squeezing or perhaps biting the spurs I2Ik into the pocket walls to form a rigid attachment. The piercing tongues I2 Ib during the above described anchoring operation contact and electrically connect with the conductor wire ends 23a and at the same time spreads said ends 23a which occupy grooves I22n provided to extend along sockets I22b to firmly wedge the conductor wires 23 about the blade end I2Io as shown in Fig. 15. Thus. here again two electrical connections are provided between the blade ends I2Ig and the conductor wires 23 while the blade portion UI which terminates short of the body portion top side I22a provides a spring adjustment like that described above for the blades 22 of fitting 20.

The bottom of the above invention, and as various changes might be made in the embodiments above set forth, it is to be understood that all matterherein set forth or shown in the accompanying draw.- ings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In a cap-plug attachment fitting of the character described, a blade formed of a strip of Sllgle thickness material having a slit wholly within an end portion thereof, a fold extending transverse the slit to provide a' double thi kness base for the blade, the contour edge 'of said slit providing a recess at said fold of the base. and piercing prongs integrally projecting from the contour edge of said slit in the same relative direction within said recess just'short of the fold, alternate prongs being formed on oppositely located edge portions of said slit. v

2. An electrical fitting ofthe character described comprising a one-piece rigidly molded body and terminal blade mounted to extend therefrom, said body having an open ng extending in from one side thereof "and parallelly aligned sockets extending in fromanother side of said body so constructed and arranged to communicate as branches with said opening, said blades each being formed of single thickness material having a lower portion provided with a slit and a folded end extending transverse said slit to provide a base of double thickness for the blade with recessed edges adjacent the fold, said blade bases having integrally formed spring portions, conductor wires passing through said opening and having bared ends thereof extending into the branch sockets, shoulders within said sockets for engaging with the spring portions on fully inserting the blade bases into the sockets to irremovably anchor said bases therein, said recessed edges on anchoring of the blade bases engaging the conductor wires for electrically connecting the latter with the blades, said sockets having grooves which said recessed edges include prongs extending within the recess for piercing through the conductor wire insulation.

4. The electrical fitting defined in claim 2 in which said recessed edges include spaced sets of piercing prongs extending within the recess, alternate prongs being formed on opposite integral edge portions of said slit.

5. An electric fitting of the character described comprising a one-piece rigidly molded body and terminal blades mounted to extend therefrom,

said body having an opening extending in from one side thereof and parallelly aligned sockets having wall grooves extending in from another side of said body so constructed and arranged to communicate as branches with said opening, said blades each having integrally formed spring portions and piercing prongs at the bases thereof,

conductor wires passing through said opening and into the branch sockets, said wire having bared ends terminating in said grooves, shoulders within said sockets for engaging with the spring portions on fully inserting the blade bases into the sockets to irremovably anchor said bases therein, said piercing prongs engaging the conductor wires for electrically connecting the latter with the blades, and contact making means integrally formed from the blade base and bent out of the planes of said bases to extend into said grooves for engaging said conductor wires bared end to electrically connect the latter with the blades when in anchored position.

6. The electrical fitting defined in claim 5 in which said blade bases have recesses on the edge portion of which piercing prongs are integrally formed to extend in the same general direction wholly therein.

'7. The electrical fitting defined in claim 5 in which said piercing prongs are located in a recess provided at the end of each blade base, adjoining prongs being formed to extend from widely ing in from one side thereof and parallelly aligned sockets extending in from another side of said body and communicating with said opening, said sockets for engaging and expanding said base portions so constructed and arranged that said expanded blade portions grip the ends thereof in the pockets to irremovably anchor the blades in rigidly mounted positions and for confining the conductor Wires to positively engage with said last mentioned piercing prongs on said expansion said blade ends while a remainder of said piercing prongs is located to electrically connect with said bared end of the wire at a spaced distance from said first mentioned electrical connection. 9. The electrical fitting defined in claim 8, in which said blades are each constructed of single thickness material having a lower portion provided with a slit within an end portion thereof and a fold extending transverse the slit to form said expandable base of double thickness with said rongs on recessed edges of the slit.

JOHN PETRY. 

